LS Gen III Engine Wiring Systems 1997-2007

Author: Mike Noonan Published by: Car Tech ISBN: 978-1-61325-701-2

I’ve mentioned the automotive ‘black arts’ in the past, with particular emphasis on automatic transmissions, but there is another area that is similarly shunned by the average home mechanic and that is automotive electronics. Mindful that General Motors’ LS-series V8 is one of the most popular engine swaps in use today, for both muscle cars and hot rods, this comprehensive volume aims to demystify the wiring and computerised electronic controls that enable this powerful motor to operate reliably and efficiently.

It commences with wire harness basics, discussing plugs, terminals and the different types and grades of wire used. This progresses on to the materials used and then the necessary equipment required, primarily wire crimping tools. Quality control is important, so this is covered next, explaining how to utilise these tools to wire the engine.

Then things get serious. The engines are operated by Powertrain Control Modules (PCMs), basically drive-by-wire computer systems that tell the motor what to do and when via multiple sensors.

There are three extensive chapters on the three main PCMs used between 1997 and 2007. Coloured wiring diagrams and flow charts with supporting photos help explain how these work and how they are calibrated and tuned. This is technical stuff, but the clear text helps to explain what’s going on. If you are attempting rebuilding or installing an LS Gen III engine this will be an essential guide to aid you in getting the electronics to work properly. I suspect most of us will leave it to the experts.